Update Travis config

Author: wouterj

.travis.yml

@@ -20,21 +20,25 @@ matrix:
   include:
     - php: 5.6
       env: SYMFONY_VERSION=2.3.*
-    - php: 5.6
-      env: SYMFONY_VERSION=2.5.*
     - php: 5.6
       env: SYMFONY_VERSION=2.7.*
     - php: 5.6
-      env: SYMFONY_VERSION=3.0.*
+      env: SYMFONY_VERSION=2.8.*
+    - php: 5.6
+      env: SYMFONY_VERSION="3.0.x-dev as 2.8.x-dev"
   allow_failures:
     - php: 5.6
       env: SYMFONY_VERSION=2.7.*
     - php: 5.6
-      env: SYMFONY_VERSION=3.0.*
+      env: SYMFONY_VERSION=2.8.*
+    - php: 5.6
+      env: SYMFONY_VERSION="3.0.x-dev as 2.8.x-dev"
 
-before_script:
+before_install:
+  - if [ "$TRAVIS_PHP_VERSION" != "hhvm" ]; then echo "memory_limit = -1" >> ~/.phpenv/versions/$(phpenv version-name)/etc/conf.d/travis.ini; fi
   - composer self-update
-  - composer require symfony/symfony:${SYMFONY_VERSION} --prefer-dist
+
+install: composer require symfony/symfony:${SYMFONY_VERSION} --prefer-dist
 
 script: phpunit --coverage-text